Predictors of of arrythmia in adult patients with Ebstein anomaly

Abstract Objectives The objective of this study was to evaluate the incidence and risk factors for arrhyhthmias in adult patients with Ebstein anomaly (EA). Methods Retrospective observational study of a multicenter cohort of 123 adult patients with EA. Demographic, clinical and echocardiography data at their first visit at the Adult Congenital Heart Disease Unit were collected. Free-event survival was assessed with Kaplan Meier curves and differences between groups using the log-rank test. Predictors of arrythmia were assessed using Cox regression analysis. Results Median follow up (FU) was 6 (IQ 2–12) years and the median age at the end of FU was 47 (IQ 33–60) years. 61.8% (n=76) were women and 68 patients (55%) had associated atrial septal defects. A total of 43 patients (34%) were repaired and 11 (8.9%) required reoperation. During FU 40 patients (32.5%) had supraventricular arrhythmias (SA), mainly atrial flutter (n=19; 15.6%) and atrial fibrillation (n=14; 11.5%); 12 patients (9.8%) developed high-grade atrio-ventricular block (AVB). In the multivariate analysis, the baseline variables associated with the appearance of SA were history of cyanosis (HR: 2.269 (1.104–4.666); p=0.026) and NYHA functional class ≥ II at baseline (HR: 2.620 (CI: 1.062–6.465); p=0.037). For high-grade AVB, the associated variable was tricuspid valve implant during FU (HR: 7.993 (CI: 1.396–45.770); p=0.020). Conclusions Arrhythmias, particularly SA, are a common complication in adult patients with EA. Patients with a NYHA functional class ≥ II at baseline and those exposed to cyanosis are more prone to develop SA during FU, whereas patients requiring tricuspid valve implant are at increased risk of developing high-degree AVB. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Hospital Vall d'HebronHospital Univertsitario Virgen del Rocío